Warm All Over

There's a lot of information about insulation out there and even more confusion. Read on to find out the differences between certain insulations.

By Nick Bajzek, Products Editor

November 01, 2007

Spray-in foam insulation products use a blowing agent to help the material expand to many times its size when applied.Photo credit: BASF

We're building homes smarter and tighter, and the end result is lower energy costs passed onto our customers. But when it comes to the insulation your company is using, does it pay to stick with tried-and-true fiberglass batts or chase higher R-values and go with a spray or blown-in system? Luckily the industry has moved on from the days of nogging, so builders have a wide selection of insulation products to investigate.

The first measure of insulation performance is the R-value, which is derived from standardized tests that determine how well the materials resist heat flow and air infiltration. Current standards in most parts of the U.S. call for at least R-13 exterior walls and R-38 ceilings. It's no coincidence that R-values are the first numbers a manufacturer will trot out to the public. But depending on the climate, quality of work and the rest of the building envelope, an R-value can become quite relative. Prices have come down with some alternate insulation products, but there's a bit of a trade-off: as the R-value goes up, so does the cost.

A majority of home builders still uses fiberglass batts as the first line of defense against air infiltration, but it's not necessarily known as being green — what your home buyers might be asking for. Increasingly, the materials we put inside our walls and ceilings can be categorized as "green"; recycled newsprint, soybean-based blown-in insulation and other sustainable methods and materials are much more commonplace than they were even five years ago.

Fiberglass insulation is still the most commonly applied method of keeping the drafts out and the heat in.Photo credit: Aquaset

It was the housing boom and successive green movement that gave the insulation industry a kick in the pants. And sometimes it wasn't what the manufacturers put into their products so much as what came out. New formulas removed or replaced environmentally harmful or hazardous ingredients. On a smaller but no less important scale are natural products that form the basis of insulation like cotton, wool and soybeans.

Although there is no perfect insulation method yet, there's a range of products that can meet your company's needs and budget. Use the chart on the following pages to get a quick run-down of the major choices the industry has to offer.

Closed Cell

Open Cell

Fiberglass batts

Cellulose

Mineral Fiber

Soybean-Based

Properties:

Cells inside the insulation resemble inflated balloons

Open-cell spray foam is found in densities ranging from 0.4 to 1.2 lbs./ft3.

Composed of Silica spun into fibers

Made from recycled paper and paper waste with up to 20% of the material composed of ammonium sulfate or boric acid

Has the look and feel of fiberglass

Rigid or flexible soy-based polyurethane plastic created from isocyanate and soybean oil-based polyol